JPH11222733A - Production of polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing polyester fibers sparingly causing filament breakage, yarn breakage and fluff even in a highs-peed yarn-making process where a spinning speed is not less than 2,500 m/min., and excellent in post-processability. SOLUTION: When spinning polyester fibers at the speed of >=2,500 m/min., the method of this invention is to give spun fibers a lubricant having the instataneous permeability IP (defined in the following formula) of <=3.5 and then to wind them: IP=B/A, where A is the permeation time of ethanol (sec.) and B is the permeation time of lubricant emulsion (sec.).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyester fiber, and more particularly, to a method for producing a polyester fiber having a spinning speed of 2500.
The present invention relates to a method for producing a polyester fiber having good post-processability with good spinning property in high-speed spinning at m / min or more.

[0002]

2. Description of the Related Art Thermoplastic synthetic fibers typified by polyester fibers are cooled and solidified after melt-spinning in a spinning process, and then an aqueous or non-hydrous oil agent is applied. The oil solution applied at the time of spinning imparts smoothness, bundling property, and antistatic property to the yarn, and improves the processability at the time of spinning and post-processing.

[0003] On the other hand, with the progress of the spinning technology and the demand for cost reduction, the speed of the spinning process has been increased. However, there is a limit to the oil film strength and adhesion of the oil agent applied to the yarn with respect to the speeding of the running yarn. That is, since the oil does not instantaneously penetrate into the interior of the yarn, sticking spots are generated, which eventually causes troubles such as breakage of single yarn and fluffing during yarn production or post-processing. Therefore, although the productivity is improved and the cost can be reduced by increasing the speed, there is a problem that the operability and the quality of the fabric obtained by knitting and weaving the manufactured yarn are rather deteriorated.

In order to solve these problems, Japanese Patent Laid-Open Publication No.
Japanese Patent Application Laid-Open No. 8-220822 discloses a method for improving the uniform adhesion of an oil agent by defining the molecular weight and composition of the oil agent component. Since the polyether component used here is terminally blocked with a phenol derivative, the stability of the solution is poor when applied to the fiber with a water emulsion or an aqueous solution, and the oil agent and water are separated,
On the contrary, there is a problem that it causes adhesion spots. Also,
Japanese Patent Application Laid-Open No. Sho 62-97908 discloses a method in which a fiber is vibrated immediately after application of an oil agent. In this method, a device for applying ultrasonic waves is required, and 2500 m
For high-speed spinning at speeds of more than / min, contact with this device
Single yarn breakage or fluffing occurs.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and reduces the occurrence of single yarn breakage, yarn breakage, and fluff in high-speed spinning at 2500 m / min or more, and improves yarn-making properties. Good, and guide,
An object of the present invention is to provide a method for producing a polyester fiber which is free from single yarn breakage, yarn breakage and fluff even when it is rubbed in contact with a needle portion.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that it is not enough to improve only the components of the oil agent and the method of applying the oil agent. The present inventors have found that the properties greatly contribute to the yarn-making properties, and have reached the present invention. That is, when the polyester fiber is spun at a speed of 2500 m / min or more, the instantaneous permeability (IP) defined by the following formula is applied to the spun fiber.
The present invention provides a method for producing a polyester fiber, characterized in that after applying an oil agent having a viscosity of 3.5 or less, winding is performed. IP = B / A where A: Permeation time of ethanol (unit: second) B: Permeation time of oil agent emulsion (unit: second)

The values A and B in the above equation are measured by the following method. First, after refining with pure water at 60 ° C., the dried fiber 50d / 18f is used as a warp, and the same treated fiber 75d / 36f is used as a weft, and the warp density is 132 yarns / 2.
54cm, polyester fabric was woven in plain weave with weft density 76 present per 2.54 cm, from the position of the fabric above 3 cm, than when gently 0.03 cm ³ dropwise ethanol of primary reagent, until completely penetrate the fabric The value obtained by measuring the time (unit: seconds) is defined as the permeation time A of ethanol. Next, using the same method as described above, the oil agent in the form of a 10% by weight aqueous emulsion was dropped, and the permeation time was measured, and the time (unit: seconds) from the time of dropping until complete penetration was measured. Time B. According to the test of the present inventors, when the fineness, the number of filaments, the weaving density, etc. of the fibers constituting the fabric change, the above A and B change. However, if A and B are measured using the same fabric, the IP value (B / A)
Since there is almost no change, the configuration of the cloth can be set arbitrarily.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The present invention is mainly directed to a polyester whose main repeating unit is ethylene terephthalate, for example, a fiber made of polyethylene terephthalate. When producing a polyester fiber at a spinning speed of 2500 m / min or more, the IP at the time of adhesion is 3.5 or less. It is necessary to apply an oil agent that is When the IP value of the oil agent to be applied to the fiber exceeds 3.5, there is no problem when spinning at less than 2500 m / min, but when the spinning speed is 2500 m / min or more as in the present invention, the cut yarn and fluff may be cut. It occurs frequently and cannot be stably formed, and the post-processability of the obtained fiber is also poor.
In the present invention, the single fiber fineness or multifilament fineness of the fiber to be spun is not particularly limited, but when the single fiber fineness is 1.5 denier or less, particularly 1.0 denier or less, the effect becomes remarkable.

The composition of the oil agent used in the present invention is arbitrary as long as it satisfies the above characteristics. There are the following methods for satisfying the value of the present invention by lowering the IP value than a general oil agent. For example, as an oil agent for use in false twisting, polypropylene oxide (P
O) / polyethylene oxide (EO) as a main component, and an alkyl sulfonate N
a salt, an anionic surfactant such as an alkyl phosphate K salt, and other additives to which a nonionic surfactant is added are used. In order to make the IP value satisfy the present invention, It is preferable to use a PO / EO copolymer having an average molecular weight of 2000 or less and a PO / EO copolymerization ratio of 60/40 or less.

The IP can also be reduced by adding a nonionic surfactant such as an alkyl ether of polyoxyethylene or an alkyl ester of polyethylene glycol. It is preferable to add 3% by weight or more based on the total weight of the oil component. Further, an anionic surfactant alkylsulfonate Na
Even if a large amount of salt is added, the above-described effects can be obtained. However, when a large amount of the alkyl phosphate K salt is used as an antistatic agent, the IP value tends to increase, so that the amount of addition must be limited to a range where the IP value falls within 3.5 or less. In some cases, mineral oil or fatty acid ester is added as a base component in order to improve the smoothness of the fiber.
There is no problem if the value is within the range of 3.5 or less.

[0012]

According to the present invention, the oil agent having an IP value of 3.5 or less adheres to the spun fiber, so that even at high speed spinning at a spinning speed of 2500 m / min or more, the oil agent instantaneously and uniformly adheres to the inside of the yarn. Therefore, it is possible to reduce the occurrence of single yarn breakage and fluff during spinning and post-processing.

[0013]

Next, the present invention will be described specifically with reference to examples. The measurement and evaluation of the characteristic values in the examples were performed as follows. (1) Spinning operability A spinneret was attached to a 4-spindle spindle and spinning was performed continuously for 5 days, and the average number of yarn breaks per day at this time was evaluated by the following three ranks. It should be noted that only 合格 was judged as acceptable. ○ (good): less than 1 time △ (slightly bad): less than 1 to 3 times × (bad): 3 or more times (2) False twisting operability Using a 20-weight false twisting machine, continuous stretching temporary for 3 days Twist,
The number of cut threads generated was converted per day. The evaluation was made in the following three ranks. It should be noted that only 合格 was judged as acceptable. （(Good): less than 2 times △ (slightly bad): less than 2 to 4 times × (bad): 4 or more times (3) Frequency of fluff (single yarn breakage) Visual evaluation: the total amount of cheese that was rolled up The generated fluff was visually observed, and the number of counted fluff was converted to 1 kg. Where the number of fluff
0.6 parts / kg or less was regarded as a pass. Warping machine evaluation: 160 yarns were randomly extracted from the obtained drawn yarn, and the fuzz generation frequency before and after the rubbing treatment by the method shown in FIG. 1 was evaluated in the following manner. Using a DSJ 21-21-OPW type warping machine manufactured by Tominaga Machinery Co., Ltd., warping is performed under the conditions of a yarn speed of 400 m / min and a sample length of 125,000 m. Counted with -32AS type fluff detector. From the total warping length of 2 × 10 ⁷ m, the number of fluffs (single yarn breaks) was converted per 10 ⁶ m. Here, fuzz evaluation criteria, pass less than 0.2 pieces / 10 ⁶ m for pre rubbing treatment, for after rubbing treatment and passed less than 0.4 pieces / 10 ⁶ m, which exceeds this non Passed.

Examples 1 to 3 and Comparative Examples 1 to 3 A polyethylene terephthalate chip containing an intrinsic viscosity [η] of 0.69 and 0.45% by weight of titanium dioxide was dried by a conventional method, and the temperature was measured using a conventional melt spinning machine. 295 ° C, discharge rate
At 42 g / min, the extruded fiber was extruded from a spinneret having 72 pores having a diameter of 0.22 mm and cooled and solidified by an air flow. Then, 0.5% by weight of the oil agent shown in Table 1 was applied based on the fiber weight. Spinning speed
The yarn was taken out at 3600 m / min to obtain a highly oriented undrawn yarn (POY) composed of cheese wound at 105 d / 72 f and 12 kg.

This POY is manufactured by Teijin SDS-8 false twisting machine 20.
Using a weight, false twist speed 700 m / min, stretch ratio 1.48, D /
Y (circumferential speed of disk / speed of fiber) 1.709, heater temperature
Under the condition of 215 ° C., continuous stretch false twist was performed for 3 days. Table 1 also shows the operability of spinning and drawing false twisting and the results of evaluating the generation of fluff on the end face of the cheese.

[0016]

[Table 1]

As is clear from Table 1, the IP value is 3.0,
In Examples 1 to 3 using the oils of 3.4 and 2.3, the number of cut yarns during spinning and drawing false twist was small, and the number of fluffs generated at the end face of the cheese was as small as 0.2 to 0.6 pieces / kg.
Fibers having good post-processability were obtained. On the other hand, if the IP value is
In Comparative Examples 1 and 3.7 of 3.7 and 6.0, yarn breakage during spinning and drawing false twisting and the number of fluffs generated during drawing false twisting were large. Further, in Comparative Example 3 having an extremely high IP value of 8.1, the number of cut yarns was large, and the number of fluffs generated was too large to be evaluated.

Examples 4 to 6 and Comparative Examples 4 to 5 Using the above-mentioned polyethylene terephthalate and a conventional melt spinning machine, at a temperature of 295 ° C., a discharge rate of 39.5 g / min and a caliber of 0.22
After extruding from a spinneret having 72 micropores, and cooling and solidifying the spun yarn by an air flow, 0.5% by weight of each of the oil agents shown in Table 2 based on the fiber weight is applied, and the speed is 3600 m / min.
It was wound around a heating roller at 93 ° C., and subsequently stretched with a heating roller at 121 ° C. to obtain a spin draw yarn of a 75 kg / 72 f, 12 kg package.

Of the spools obtained above, 160 spools were randomly extracted and the frequency of fluff occurrence was evaluated using a warping machine. Also, using the same spool as the device shown in FIG.
Unwinding speed 200m / min, contact angle θ80 °, supply tension 10g
And then wound with a winder 6 to obtain about 1 kg of cheese. Using the obtained cheese, the frequency of occurrence of fluff after rubbing with a needle for tubular knitting was evaluated as described above. Table 2 also shows the operability during spinning and the evaluation results of the frequency of fluff generation before and after the rubbing treatment on the needle for knitting.

[0020]

[Table 2]

As apparent from Table 2, the IP value is 1.8,
In Examples 4 to 6 using the oils of 2.3 and 3.1, the spinning operability was good, and the generation of fluff was small. Further, the number of fluffs generated by rubbing with the needle for tubular knitting was almost the same as that of the untreated result, and both the spinning property and the post-processability were good.
On the other hand, in Comparative Examples 4 and 5 having IP values of 4.2 and 5.0, the number of cut yarns at the time of spinning was large, and a large number of fluffs were generated even with an untreated drawn yarn.
Furthermore, the frequency of fluff generation after rubbing with the needle for tube knitting was significantly increased as compared with the untreated needle.

[0022]

According to the present invention, by applying an oil having an IP value of 3.5 or less, even in high-speed spinning at 2500 m / min or more, the oil can instantaneously penetrate into the inside of the yarn without unevenness and adhere to the oil. It becomes possible to suppress the generation of cut yarns and fluffs due to spots, and to obtain good yarn-making properties, and the obtained fibers have excellent post-processing properties.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a method of performing a rubbing process before evaluating the frequency of occurrence of fluff (single yarn breakage) with a warper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cheese 2 Guide 3 Supply roller 4 Needle for knitting 5 Winding cheese after rubbing 6 Winding winder θ Contact angle

Claims (1)

[Claims] When spinning a polyester fiber at a speed of 2500 m / min or more, the spun fiber is provided with an oil agent having an instantaneous permeability (IP) defined by the following formula of 3.5 or less, and then wound up. Characteristic method for producing polyester fiber. IP = B / A where A: Permeation time of ethanol (unit: second) B: Permeation time of oil agent emulsion (unit: second)